The invention relates to an electric motor and/or generator of the kind provided with a central end flange serving for fastening it to a bracket or a portion of a machine or implement, and to the provision of integral means for its lateral disposal, with the object of placing its shaft in alignment with a gear, of tensioning a belt drive or for other purposes.
Although the invention relates to both electric motors and generators in the same manner, reference in the following will be made to "motors" only, including both kinds of electric machinery, in order to simplify the description and explanation. For the same reason the object of shifting of the motor axis in lateral direction will be referred to only in relation to belt tensioning, although, as mentioned before, there may be other purposes.
Tensioning of a belt drive connecting the motor pulley to a driven pulley is either carried out by means of a tensioning sheave serving to take up the slack, or by moving the electric motor along slotted slide rails. In the case of small motors the entire motor is mounted pivotally, permitting the belt drive to be tensioned by moving the motor about its pivot. In the case of flanged motors the best known solution is by means of a tension sheave, but this has the drawback of consuming additional energy by friction and by bending the belt in outward and inward direction during every passage. Another solution is by sideways shifting of the entire bracket holding the motor which, due to its construction, is rigidly fastened to the bracket.
It is the object of the present invention to dispense with both above kinds of belt tensioning by providing the motor itself with tensioning means permitting a certain range of shifting of the motor shaft in order to tension the belt or to bring a gear wheel on the shaft into proper engagement with a driven gear.
It is another object to provide simple tensioning means which lend themselves to ready adjustment without application of force, whilst maintaining the pulley or gear in its proper alignment with the driven pulley or gear.
And it is still another object to provide these tensioning means at no extra cost for the customer, by their integration in the motor construction during manufacture.